diff --git a/src/knx/bau_systemB.cpp b/src/knx/bau_systemB.cpp
index b0e7ef8..53548e6 100644
--- a/src/knx/bau_systemB.cpp
+++ b/src/knx/bau_systemB.cpp
@@ -299,7 +299,7 @@ bool BauSystemB::restartRequest(uint16_t asap)
 {
     if (_appLayer.isConnected())
         return false;
-    _restartState = 1; // order important, has to be set BEFORE connectRequest
+    _restartState = Connecting; // order important, has to be set BEFORE connectRequest
     _appLayer.connectRequest(asap, SystemPriority);
     _appLayer.deviceDescriptorReadRequest(AckRequested, SystemPriority, NetworkLayerParameter, asap, 0);
     return true;
@@ -307,15 +307,15 @@ bool BauSystemB::restartRequest(uint16_t asap)
 
 void BauSystemB::connectConfirm(uint16_t tsap)
 {
-    if (_restartState == 1 && tsap >= 0)
+    if (_restartState == Connecting && tsap >= 0)
     {
         /* restart connection is confirmed, go to the next state */
-        _restartState = 2;
+        _restartState = Connected;
         _restartDelay = millis();
     }
     else
     {
-        _restartState = 0;
+        _restartState = Idle;
     }
 }
 
@@ -323,27 +323,27 @@ void BauSystemB::nextRestartState()
 {
     switch (_restartState)
     {
-        case 0:
+        case Idle:
             /* inactive state, do nothing */
             break;
-        case 1:
+        case Connecting:
             /* wait for connection, we do nothing here */
             break;
-        case 2:
+        case Connected:
             /* connection confirmed, we send restartRequest, but we wait a moment (sending ACK etc)... */
             if (millis() - _restartDelay > 30)
             {
                 _appLayer.restartRequest(AckRequested, SystemPriority, NetworkLayerParameter);
-                _restartState = 3;
+                _restartState = Restarted;
                 _restartDelay = millis();
             }
             break;
-        case 3:
+        case Restarted:
             /* restart is finished, we send a discommect */
             if (millis() - _restartDelay > 30)
             {
                 _appLayer.disconnectRequest(SystemPriority);
-                _restartState = 0;
+                _restartState = Idle;
             }
         default:
             break;
diff --git a/src/knx/bau_systemB.h b/src/knx/bau_systemB.h
index 546135d..6ad0300 100644
--- a/src/knx/bau_systemB.h
+++ b/src/knx/bau_systemB.h
@@ -65,6 +65,14 @@ class BauSystemB : protected BusAccessUnit
     void updateGroupObject(GroupObject& go, uint8_t* data, uint8_t length);
     void nextRestartState();
 
+    enum RestartState
+    {
+        Idle,
+        Connecting,
+        Connected,
+        Restarted
+    };
+
     DeviceObject _deviceObj;
     Memory _memory;
     AddressTableObject _addrTable;
@@ -76,6 +84,6 @@ class BauSystemB : protected BusAccessUnit
     TransportLayer _transLayer;
     NetworkLayer _netLayer;
     bool _configured = true;
-    uint8_t _restartState = 0;
+    RestartState _restartState = Idle;
     uint32_t _restartDelay = 0;
 };
\ No newline at end of file